1. Field of the Invention
The present invention relates to a multilayer type inductor and a method of manufacturing the same.
2. Description of the Related Art
In terms of electronic parts using a ceramic material, there may be provided a capacitor, an inductor, a piezoelectric element, a varistor, a thermistor, or the like.
Among these ceramic electronic parts, the inductor is one of the main passive elements constituting an electronic circuit, and serves to remove noise or constitute an LC resonance circuit.
This inductor may be manufactured by winding a coil around a ferrite core or printing a coil, and then forming electrodes at both ends thereof, or by printing internal electrodes on a magnetic material or a dielectric material and laminating them.
Inductors may be classified into several types, such as a multilayer type, a winding type, a thin film type, and the like, according to a structure thereof, the multilayer type being widely employed.
The multilayer type inductor is manufactured to have a laminate form in which a plurality of ceramic sheets, formed of ferrite or low-k dielectric, are laminated.
A coil type metal pattern is formed on each ceramic sheet. Coil type metal patterns formed on respective ceramic sheets are sequentially connected through conductive vias formed in the respective ceramic sheets, and overlap in a laminating direction, to constitute a coil having a helical structure.
Both ends of the coil are drawn out to an external surface of the laminate and connected to external terminals.
The multilayer type inductor may be manufactured as a separate component in a chip type, or may be formed together with other modules while it is embodied in a board.
Generally, the multilayer type inductor has a structure in which a plurality of magnetic layers having metal patterns thereon are laminated. The metal patterns are sequentially connected by via electrodes formed on the respective magnetic layers so that they overlap in a laminating direction, resulting in a coil having a helical structure.
Since this coil of the multilayer type inductor is surrounded by a magnetic material, the magnetic material around the coil is likely to be magnetized when a high current is applied thereto.
In addition, a part around the coil is magnetized, and thus, an inductance (L) value of the inductor is changed, thereby deteriorating capacitance characteristics of the inductor.